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I was wrong to say that SC should not change with the DISC pot. SC is the (inverted) SA or SB logic function, and the disc pot changes SB directly. Therefore turning the DISC pot should change SC.
Somewhere in the back of my mind that previous statement did not seem right.
(I need a long vacation.)
Hi
this figure for wave of GND and pin6 ne5534.
mr porkluvr i return multitern(discrimination)and sb dont change ,also sa and sb dont change when the output of 555 is changing.BECAUSE i am sure my problem in U3(second 453
you say maybe one 4148 destroyed but when in pin 9 second 4538 not output how is it work?
i put my picture step by step and waiting.
thanks
I don't know what your NE5534-6 should look like. I don't care what it looks like. You should concentrate on one problem at a time. Do you think you have a CD4538 timing problem?? I think you should WORK ON THAT, and fix it if it is broken. After that you can chase other problems.
SB is not supposed to change with DISC pot. SC will change but not SB.
If you view only a single pulse you will not see any change in SA SB or SC as you change either 555 PPS or 555 PW. If you would adjust the timebase control on the oscilloscope so that you can see more than one pulse at the same time, then when you change 555 frequency you should see a change in spacing between pulses... but you should really checking that at the 555 pin-3.
If you are concerned with the 555 potentiometers, then look at the 555-3 signal.
I don't understand why georgi had you probe at the start of the signal chain and then work to the end. I think that approach is exactly backwards for troubleshooting purposes. It only adds confusion and that is undesirable.
What I said before about looking at SA SB and SC still holds true. In my opinion, if those signals are good, then you do not need to look at all the other 4538 signals.
You should adjust the scope so that you can look at more than one cycle at the same time. That will give you a better overall view of the situation. If you want to diagnose a possible timing problem and you have your scope set to see only a single pulse, then you are wrong.
Hi
this figure for wave of GND and pin6 ne5534.
mr porkluvr i return multitern(discrimination)and sb dont change ,also sa and sb dont change when the output of 555 is changing.BECAUSE i am sure my problem in U3(second 453
you say maybe one 4148 destroyed but when in pin 9 second 4538 not output how is it work?
i put my picture step by step and waiting.
thanks
It is really hard to analyse what you have. Too much, umh, information.
Please, it would be helpful in the future if you turned the oscilloscope intensity down a little bit so that the scope trace is not so bright and blurry. I know your camera has some blurriness, but turn down the scope intensity.
Listen up, this is important:
You MUST take advantage of the oscilloscope having two channels. Use two probes, one for each channel. It would be informative if the scope be set to trigger off the signal on ch1. The ch1 signal trace position should remain stationary. Then, whatever is probed on ch2 can move left or right (as you turn the pots) and be viewed in temporal (time) relationship to ch1. Otherwise, you cannot see temporal relationships because you have no temporal reference.
Otherwise if you use only a single channel, while you can see if a pulse gets wide or narrow, you will not be able to see if one pulse is moving in relationship to another.
When you use two channels then you will be able to watch relative movement between the two signals being probed. So... if you only have access to one single probe, then you really do need to beg borrow or steal, to obtain another one!
Time out, and I'll look at what what you posted to see if I can see anything telling.
Hi
this figure for wave of GND and pin6 ne5534.
mr porkluvr i return multitern(discrimination)and sb dont change ,also sa and sb dont change when the output of 555 is changing.BECAUSE i am sure my problem in U3(second 453
you say maybe one 4148 destroyed but when in pin 9 second 4538 not output how is it work?
hi guru
look and give your opinion
look ,i work like said in your picture,again step by step
this is step by step,just secon picture for pin6,11,10 frist 4538
step1,step2,3,4,5,6
Thanks for those tips, georgi. Maybe when mohandes gets past the timer section you will help him with setting up the summer/integrator channels (I hope, I hope).
my dear friend porkluvr
ok i want put my pictures (for today)but i can say for you v(tx) is ok,v(sa)is ok,v(sb)not good but i dont know i can adjustment that by discrimination again measure that tomprrow,and v(sc)like #106.
just a question you say put all potentiometers set at ~50%, should adjust pps and pw and do you adjust them,
I do not think I said for you to put your pots at 50%, but that is what my simulation did, and it probably is a good idea for starters. The pulse timing formula for CD4538 is simply t=RC so there is not really any need to simulate at more than one pot position. To do the math is simple.
Signal sc is the (inverted) sum of sa and sb.
The 4538 Q and /Q signals are complementary outputs (pins 6,7 and 10,9). As one goes high, the other one goes low, with a duration according to the timing formula.
If you probe sc and determine that its duration does not equal the sum of sa and sb, then you should make sure the two diodes are oriented correctly.
When I said I might accomodate your requests for probing "this" circuit, what I was referring to was what I have already drawn. I have other things to do besides add more components to the simulation. It is what it is.
Learn to use the basic LTspice program. You can get the CD4000 components library by first joining the LTspice Yahoo group, then download the CD4000 parts library from the Files section. I will help you learn to use the CD4000 library (and also LTspice) if you request, but I can't learn it for you. And I will not send you my simulation file because I would also have to send my modified CD4000 models and symbols libraries, for it to be of any use. That is very time consuming. And then you would be bombing me with questions because it involves advanced concepts. Please learn to use the basic program first.
mohandes , You understand ? STEP BY STEP![ATTACH]24616[/ATTACH]
Hi mr georgi my friend
how ever i measure all and say my problem today i measure number that you certain,and put for you by this names.
i think this is good idea man.
and i know step by step and measure all point but when i dont know how solve my problem (or maybe correct and i cant analyse my figures)
but a few time ago i connet all my pcb and work but the discrimation not work (just green led become ON)and the deeps on the air by my coil(370Uh)near 5cm .
thanks
to night i send my result and i just can say thanks for all guru and you georgi
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